This book is packed with a lot of information, but you might only find all of that value if you have a group to search together.
This was a hard decision between three and four stars for me. I really like this book but I suspect that a large part of why I really like this book is because of the book club where I discussed that book.
There is a lot to discuss here. Drucker discusses in depth his business philosophy and where he sees the role of management. He has a great deal of tactical advice to manage your own effectiveness. He has honest insights about the role of volunteering in a knowledge workers life. More than a decade after his death (and many many more decades after the original publishing of this work) the lessons are still true. Since the time of original publishing much of these foundational principles have spawned their own books around concepts that Drucker nonchalantly mentions.
There are a few areas that did not hold up over time. Drucker asserts that we will shortly reach the post-capitalistic age of society and I'm still waiting on that one. Others are more true: he expects that knowledge workers being the prime capital will lead to companies who cater their work practices and balances specifically to those values.
Ultimately, I had to go with the lower of the two ratings because I'm confident that without a group to dig into the principles of the book I would not have appreciated the content as much. Overall, I'm glad that I read this book but Drucker's light touch left me wishing that I was just going straight for some of the newer books on the specific topics. I still came out with some tactical advice that I'm using to manage my own effectiveness. I'm glad to be able to add Drucker to list of voices in my head when I am analyzing business concepts, but I understand he is one of many.